What was the occupation of Lance Corporal Jack Jones in the British TV sitcom 'Dad's Army'?

Dad's Army is a BBC television sitcom about the British Home Guard during the Second World War. It was written by Jimmy Perry and David Croft and broadcast on the BBC from 1968 to 1977. The sitcom ran for 9 series and 80 episodes in total, plus a radio version based on the television scripts, a feature film and a stage show. The series regularly gained audiences of 18,000,000 viewers and is still repeated worldwide.

Lance Corporal Jack Jones is a fictional Home Guard platoon lance corporal, veteran of the British Empire and butcher, portrayed by Clive Dunn in the BBC television sitcom Dad's Army. His catchphrases are "Don't panic!", "Permission to speak, sir?" and "They don't like it up 'em!". Jones also often recounts his past military experiences particularly those in Sudan and India and gives a glimpse to the military traditions and events in the concluding years of the 19th century.

Jones is known for a number of eccentric traits, such as using long, rambling explanations and anecdotes whenever he wants to make a point. He is also invariably one step behind the rest of the platoon in any drill manoeuvre.